1. Field of the Invention
The invention relates to tubular casings, preferably foodstuffs casings of regenerated cellulose, which have improved adhesion to their filling.
2. Background Information
Tubular casings of regenerated cellulose are widely used as packaging materials for foodstuffs and are thus employed on a very large scale for the manufacture of processed meat products such as sausage products. If the inside of such foodstuffs casings is used untreated, it is observed that, during sausage production, in particular the production of uncooked sausages, the sausage meat does not adhere sufficiently firmly to the sausage casing. Consequently, there is partial detachment from the sausage casing in the sausage, frequently together with an undesired formation of an oil or jelly film on the sausage material.
Moreover, because of the detaching, the foodstuffs casing no longer shrinks with the filling material, so that the sausage has a creased and unattractive appearance.
In order to overcome the disadvantages mentioned, it is usual to provide the inside of the tubular foodstuffs casing of regenerated cellulose with a coating based on chemically modified proteins, epichlorohydrin resins, polyamine-polyamide resins, urea/formaldehyde or melamine/formaldehyde resins. (U.S. Pat. No. 3 378 379 and EP-A-88308).
Admittedly, this internal finish to tubular foodstuffs casings leads to an improvement in adhesion, but this is insufficient for some applications including the production of uncooked sausages. In addition, it is observed that tubular casings internally coated in this way can strick, so that opening and filling can be greatly impeded. German Gebrauchsmuster G No. 8 436 989 teaches the addition of a lactone to an internal finish but only for preventing discolouration.